WILLIAMSON RIVER ROAD

LONE PINE ROAD

SPRAGUE RIVER ROAD

SPRAGUE RIVER ROAD

SQUAW FLAT ROAD

SPRAGUE RIVER ROAD

97

140

140

10

5

15

20

25

30

35

40

45

50

55

60 65

70

75

80

85

90

95

100

105

5

5

10

0

0

0

Kamkaun

Spring

Whitehorse

Springs

McCready

Springs

Lalo

Springs

Medicine

Springs

Brown

Spring

Qc

Qt1

Qtu

Qf2

Qls

Qls Qtf

Tbr

Tbr

Qtfp

Qfp

Qfp

Qt2

Qt3

Qmvf

Qc

Qtfp

Qc

Qmvf

Qc

Qc

Qc

Qc

Qc

Qc

Qfp

Qfp

Tbr

Tbr

Tbr Qc

Qfp

Qfp

Qfp

Qfp

Qfp

Qfp

Qfp

Qc

Qc

Qc Qc Qc

Qc

Qc

Qc

Qc

Qc

Qc

Qc

Qc

Qc

Tbr

Tbr

Tbr

Tbr

Qfu

Qfu

Qfu

Qfu

Qfu

Qfu

Qfu

Qfu

Tbr

Tbr

Qtf

Qtf

Qtf

Qtf Qtf

Qtf

Qtf

Qtf

Qtf

Qtf

Qtf

Qtf

Qtf

Qtf

Qtf

Qtf

Qtf

Qtf

Qtf

Qt2

Qt2

Qt3

Qt4

Qt4

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt2

Qt2

Qt2

Qt3

Qmvf

Qmvf

Qmvf

Qmvf Qmvf

Qmvf

Qmvf

Qmvf

Qf1

Qf3

Qf4

Qf4

Qf4

Qf4

Qf3

Qf3

Qf3

Qf4

Qf2

Qf1

Qf1

Qt4

Qt1

Qc

Qtfp

Qtfp

Qf2

Qtfp

Qtfp

Qtfp

Qtfp

Qsf

Qsf

Qtfp

Qtfp

Qc

Qc

Qc

Qw

Qw

Qw

Qw

Qt1

Qt2

Qc

Qc Qt2

Qmvf

Qtfp

Qtf

Qc

Qc

Qmvf

Qt2

Qt1

Tbr

Tbr

Tbr

Qc Qc

Qt3

Qtf

Qfp

Qtu

Qtfp

Qtfp

Qtfp

Qtfp

Qtfp

Qtf

Qtf Tbr

Qc

Qc

Qtfp

Qtfp

Qtf Qc

Qmvf Qc

Qmvf

Qc

Qtf Qmvf

Qc

Qmvf

Qtf

Qsw

Qsw

Qsw

Qsw

Qtf

Qtfp

Qtfp

Qtfp

Qtf

Qtf

Qsf

Qsf

Qls

Tbr

Qtf

Qtf Qt2

Qc Qc

Qc

Qt1

Qsw Tbr Qtf

Qf1

Qf1

Qc

Tbr

Qc

Qc

Qtfp

Qtf

Qtf

Qtf

Qtf

Qtf

Qtfp

Qc

Qtf

Qtf

Qtfp

Qt1 Qt1 Qt1

Qt1

Qt1

Qt1

Qtf

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt1

Qt2

Qc

Qt3

Qtfp

Qtfp

Qtfp

Qt1 Qt1

Qt1

Qt1

Qt1

Qtu

Qfp

Qls

Qtfp

Qtf Qtf

Qf4

Qc

Qsf

Qt1

Qtf

Qt1

Qtf

Qt1

Qtf

Qtf Qt1

Qmvf

Qmvf

Qtfp

Qtfp

Qc

Tbr

Qt1

Qtfp

Qmvf

Qtfp

Qfu

Qfu

Qc

Qc

Qtf

Qtfp

Qmvf

Chiloquin

Sprague River

Beatty

Bly

Braymill

11501000

11499100

11497500

11495600

Williamson River

Copperfield

Draw

Trout Creek

North Fork Trout Creek

Whisky Creek

South Fork Trout Creek

Snake Creek

Fivemile Creek

Long Creek

Meryl Creek

Fritz Creek

Deming

Creek

Fishhole Creek

Paradise Creek

Campbell

Reservoir

Wild

Billy

Lake

Hawks

Lake

Sprague River

North For k Sprague River

Sprague River

Sycan River

Dockney Creek

Rock Creek

Brown Creek

South

Fork

Sprague River

Sprague

River

Sprague River

FORMER

CHILOQUIN

DAM 7/1/05-1

7/1/05-2

7/2/05-1

9/14/07-1

6/26/07-3

9/12/06-2, 3

6/25/07-1, 2 6/28/07-1

6/22/07-4, 5

7/24/07-1, 2

6/23/07-1

9/13/06-1, 2

9/13/07-3 9/13/06-3

6/28/05-1

9/22/05-6

9/20/06-4, 5

9/15/06-2

9/15/06-1a, b

6/28/07-2

9/12/06-1a

9/20/06-1,2, 3

9/22/05-1, 2

9/22/05-3, 4 Saddle Mountain

Knot Tableland

Round

Mountain

Cliney 

Flat

Ferguson

Mountain

Medicine

Mountain

Council

Butte

Spring

Butte

Bug

Butte

Cave Mountain

Bad Lands

Buttes of the Gods

Switchback Hill

Bly

Mountain

K Davis Hill

Bly Ridge

Devil’s

Garden

Beatty Gap

S’Ocholis Canyon

Sycan Canyon

Knot Tableland

Chiloquin

Canyon

Braymill

Kamkaun

Spring

S’Ocholis

Canyon

Buttes of

the Gods Council Butte Beatty

Sycan

Lower

Sycan

Coyote

Bucket

Beatty Gap Upper

Valley South

Fork

North

Fork

0

11.4

17.2

32.4

48.2

58.0

76.8

81.0 89.6 93.2

106.3

0 0

10.6

9.8

GEOMORPHIC FLOOD PLAIN STUDY REACHES

Sprague River

Basin

Study

area

OREGON

Portland

Klamath Falls

Geomorphic Flood Plain (Holocene)—Area of Holocene channel migration; channels and active flood plains along the North Fork 

Sprague, South Fork Sprague, main-stem Sprague, and Sycan Rivers. This map unit, divided into valley segments, is the area of 

the detailed mapping analysis of constructed features, historical channel change, and vegetation described in this report. This

unit encompasses the area of channels, abandoned channels, and bar-and-scroll topography evident on the 2004 Light 

Detection and Ranging (lidar) topographic data. The presence of main-stem channel topographic features distinguishes this 

unit from the main-stem valley fill unit. Soils are typically poorly drained and include volcanic-ash-rich Mollisols dominated by 

the Klamath-Ontko-Dilman series (Cahoon, 1985). Stratigraphy exposed on eroding streambanks and from augering show that 

these flood-plain deposits almost everywhere formed after the 7,700 cal yr BP (calendar years before present) Mazama 

eruption. In places, particularly along the lower Sycan River (Lind, 2009) and the North Fork Sprague River, stratigraphic 

relations show at least two episodes of flood-plain erosion and rebuilding in the last 7,700 cal yr BP. The geomorphic flood plain 

has formed in the last 7,700 cal yr BP from a combination of channel migration, channel avulsion, and lateral and vertical 

accretion of bedload and suspended load deposits. The geomorphic flood plain is mapped on the basis of morphology and does 

not necessarily correspond to a specific height above the channel or areas subject to flooding at a specific frequency. Locally 

includes springs and associated wetland deposits within the area of Holocene channel migration. 

Main-Stem Valley Fill (Holocene)—Flood plain and basin areas outside of active channel areas of the geomorphic flood plain, but 

historically are subject to overbank flooding. Low-gradient planar surfaces totaling 28 km2 (square kilometers) occupy broad 

areas flanking the Sprague River corridor, particularly in the Kamkaun Spring, S'Ocholis Canyon, and Buttes of the Gods valley 

segments. Additionally, this map unit includes bottomlands flanking the post-Mazama (7,700 cal yr BP) zone of channel 

migration (the geomorphic flood plain) in the Council Butte and Beatty-Sycan valley segments. The surfaces generally have 

soils mapped as Inceptisols or Mollisols formed in part by cumulic deposition of silt and clay during overbank flooding. Many of 

the surfaces are flooded during periods of high water, but show no evidence of hosting major channels. Many of these surfaces 

are now diked and drained. Some of these broad valley bottoms marginal to the main river course, especially within the 

Kamkaun Spring, S'Ocholis Canyon, and Buttes of the Gods valley segments, seem to be long-term sediment depocenters 

because of overall Sprague River valley aggradation, perhaps in conjunction with block faulting along the north-northwest 

trending faults transecting the lower part of the Sprague River Valley. Within the Council Butte and Beatty-Sycan valley 

segments, the valley fill unit encompasses broad tracts of seasonally inundated lowlands flanking the Sprague River, but is 

outside areas occupied by late Holocene channels. In places, this unit may correspond with low terraces mapped in the Council 

Buttes and Beatty Gap valley segments. 

Terrace (Quaternary)—Terrace deposits along main-stem Sprague River. Planar alluvial surfaces as much as 50 meters (m) 

above the active flood plain flank the Sprague River near its confluence with the Williamson River. Similarly, terraces at 

several elevations ranging as much as 20 m above the geomorphic flood plain border the Sprague River in the Chiloquin 

Canyon, Braymill, Kamkaun Spring, S'Ocholis Canyon, and Buttes of the Gods valley segments. Locally, terraces are enumerated 1 through 4 on the basis of increasing elevation (and presumably age) above the geomorphic flood plain. Isolated low 

terraces flank the Sprague River in the Council Butte and Beatty Gap segments, as well as along the lower Sycan River. The 

terrace surfaces are underlain by fluvial gravel and are generally stable features upon which Haploxeroll soils have formed, 

indicating formation of a cambic B horizon and some carbonate accumulation (Cahoon, 1985). Terrace risers locally expose 

Tertiary lacustrine sediment or other bedrock units, indicating that at least some of the terraces are strath surfaces cut into 

the soft Tertiary sediment. The positions and degree of soil development are consistent with ages of late Tertiary through 

Quaternary. Many or all of these terraces pre-date the 7,700 cal yr BP Mazama eruption, judging from the presence of Mazama 

fallout tephra in the upper parts of their soil profiles (Cahoon, 1985). Like the abandoned alluvial fans, the terraces result from 

episodic filling and incision during Quaternary downcutting of the Sprague River. Some of this downcutting may have resulted 

from broadscale base-level fall associated with integration of the upper Klamath River basin (Sherrod and Pickthorn, 1992), 

but some terrace sequences may reflect more local tectonic blockages associated with the north-northwest trending 

basin-and-range faulting affecting the western Sprague River valley segments. 

Active Tributary Flood Plain (Holocene)—Tributary channel, flood plain, and basin fill deposits in low-gradient areas subject to 

inundation, and unconfined by valley margins. Tributary channels and flanking surfaces grade to modern main-stem channels 

and flood plains, forming narrow and elongate map units extending into the uplands where channels become increasingly 

topographically confined. In some reaches, especially the Kamkaun Spring, the tributary valleys have very low, nearly 

horizontal, gradients, whereas in many locations, tributary valley flood plains have gradients approaching 5 degrees. The 

distinction with tributary fans and colluvium is primarily on the basis of plan-view morphology and slope but is locally indistinct. 

Primary soils on tributary flood plains are Inceptisols and Mollisols, which typically form in late Pleistocene or Holocene 

deposits (Cahoon, 1985).

Active Tributary Fans (Quaternary)—Shallowly sloping (less than 10 degrees) alluvial transport surfaces grading to modern 

main-stem and tributary flood plains, commonly with a singular or composite fan-shaped down-gradient terminus. These are 

active alluvial transport surfaces heading from confined tributaries, colluvial slopes and bedrock, and have formed where flow 

routes expand onto flat terraces, flood plains, and other flat bottomland surfaces. These surfaces are commonly gradational 

with colluvial slopes and valley bottomlands, but with intermediate slopes. Active fan surfaces are mantled with Haploxerolls, 

Cryorthents, Cryofluvents, Cryoborolls, and Cryaquepts soil taxonomic classes, all of which have only incipient horizon 

development in the form of translocated and accumulated carbonates and silica, consistent with late Pleistocene to Holocene 

ages. Many active fans have surfaces post-dating the 7,700 cal yr BP Mazama eruption. Active fans episodically provide 

sediment to the main-stem rivers and flood plains.

Abandoned Fan (Quaternary/Tertiary)—Incised tributary fan deposits, surfaces as much as 30 m above active channels. These 

shallowly sloping (less than 10 degrees) alluvial transport surfaces have been incised because of base-level fall. Large 

abandoned fan complexes border the southern Sprague River valley in the Buttes of the Gods and Council Butte valley 

segments. Constriction of the valley by one such fan near the settlement of Sprague River separates these two valley segments. 

Locally, abandoned fan surfaces are enumerated 1 through 4 on the basis of increasing degree of incision (and presumably 

age). The older surfaces have only isolated remnants of original transport surfaces, underlain by fluvial gravel, separated by 

younger (and lower) fan and tributary surfaces and by slopes formed in the underlying Tertiary lacustrine sediment. Some 

abandoned fan surfaces, including those south of the Sprague River Valley near Beatty and Bly, are partly formed of pumiceous 

pyroclastic flow deposits derived from Tertiary volcanic centers to the south (Sherrod and Pickthorn, 1992). Near the Sprague 

and Sycan Rivers, these tributary fan deposits are locally interbedded with main-stem fluvial channel and overbank deposits. 

Primary soil taxonomic classes on abandoned fan surfaces include Haploxerolls, Argixerolls, and Durixerolls, indicating minor 

to significant accumulations of clays, silica, and carbonate. The ages of these surfaces likely range from Pliocene to possibly

as young as early Holocene. All abandoned fan deposits, however, likely post-date the approximately 3.0 million year old Basalt 

of Knot Tableland. The abandoned fans are largely stable features that contribute little sediment directly to the modern fluvial 

system. These abandoned alluvial fans reflect overall Tertiary and Quaternary valley incision of the Sprague River valley, 

probably in conjunction with integration and incision of the Sprague River through fault-uplifted canyon segments downstream.

Active Springs and Spring Deposits (Holocene)—Active springs and associated wetland deposits. Six areas of springs and 

related features such as ponds, wetlands, and channels are within the map area but outside the geomorphic flood plain. Most 

are contiguous with the geomorphic flood plain or flanking terraces. Spring outlets with flowing water have sandy to gravel 

substrates, surrounding areas consisting mostly of saturated peat deposits formed from aquatic vegetation. Most spring 

complexes are connected to the Sprague and Sycan Rivers by sand-bed spring channels. 

Sycan Flood Deposits (Holocene)—A prominent planar surface extending south discontinuously from the lower Sycan River 

canyon to its confluence with the Sprague River. This surface stands 3 m above the active flood plain at the downstream end of 

Sycan Canyon, and descends to flood plain level near the Sycan River confluence with the Sprague River. It is underlain by as 

much as 3.35 m of bedded sand and gravel composed almost entirely of Mazama pumice. The deposits fine and thin 

downstream, where they are overlain by alternating beds of silty fine sand and sand. At their apex near the downstream end of 

the Sycan Canyon, these deposits grade to surfaces mantled with 1-m-diameter rounded basalt boulders, apparently derived 

from the canyon rim and walls and transported downstream. The soil capping these surfaces is mainly classified as an Ashy 

Typic Cryopsamment, indicating poorly developed soils formed in sandy parent materials. The pumiceous sand and gravel 

overlies organic-rich silt and clay deposits, locally peaty, and commonly containing within 10 centimeters (cm) of its top, a 

0.5-to-2.5-cm-thick layer of silt- and sand-size Mazama tephra. This fallout tephra, constrained by radiocarbon dates here and 

in other areas, resulted from the Mazama eruption of about 7,700 cal yr BP. The inference is that this terrace resulted from a 

large, pumice-laden flood down the Sycan River within a few decades or centuries of the 7,700 cal yr BP Mazama eruption. A 

plausible source for such a flood was temporary impoundment of a lake in the Sycan Marsh area, possibly by dunes of Mazama 

pumice blocking the Sycan River channel near the marsh outlet (Lind, 2009). The Sycan flood deposits are coarse, loose, and 

erode readily from disturbed sites, particularly along tall banks flanking the modern channel or flood plain.

Pond and Wetland Deposits (Holocene)—Lacustrine deposits associated with modern or historical waterbodies; only shown 

outside of the geomorphic flood plain. Several small closed depressions host seasonal to perennial waterbodies. Most are 

within areas of valley fill or occupy depressions within abandoned fans. Nearly all are used for water storage with dikes or small 

dams augmenting storage capacity.

Colluvial Slopes (Quaternary)—Hillslope colluvium and piedmont slope deposits. Steep but smooth slopes, as much as about 35 

degrees, underlain by unconsolidated regolith and formed by gravitational and alluvial transport processes such as rockfall, 

avalanching, biogenic disturbance, and sheet wash transport. Colluvial slopes typically head at steep bedrock outcrops, which 

are the source of material, and transition downslope to alluvial transport surfaces. Colluvium is locally an important source of 

coarse (gravel-size) material to the Sprague and Sycan Rivers, especially in canyon segments where much of the flood plain is 

bordered by colluvium or bedrock. The distinction of colluvial slopes and active tributary fans is locally arbitrary, but tributary 

fan slopes typically are less than 10 degrees.

Landslide Deposits (Quaternary)—Deposits of large mass movements, primarily rotational failures, usually with steep hummocky 

topography bounded on upslope margins by arcuate scarps. A few landslides are evident in the Chiloquin Canyon valley 

segment and in the lowermost part of the Sycan River canyon within the Coyote Bucket valley segment. The Sycan River canyon 

landslides likely blocked the channel, and the affected reaches traverse accumulations of large blocks of volcanic rock from 

the canyon rim. 

Undifferentiated Bedrock (Tertiary)—Irregular, typically hummocky or steep topography, underlain by Tertiary lacustrine sediment 

or volcanic rocks. This unit was mapped only where completely surrounded by mapped alluvial or colluvial surfaces.

DESCRIPTION OF MAPPING UNIT

Qw

Qc

Qtf

Qsf

Qf2

Qt4

Qt3

Qt1

Qf3

Qf4

Qf1

Qmvf

Qfu

Qtu

Qfp

Qt2

Qtfp

Qsw

Qls

Tbr

EXPLANATION

35

Water—Located outside mapped area. From National 

Hydrography Dataset

Primary channel—Mapped from 2000 aerial photographs

Contact

Flood-plain transects—Spaced every 1 kilometer, labeled 

every 5 kilometers starting from mouth of river or tributary

Sprague River Basin boundary

Streams—From National Hydrography Dataset. Not 

displayed within geomorphic flood plain

Road

Major (highway)

Minor

McCready 

Spring

DAM

6/28/07-2 Stratigraphy site—With site number(s). See

figures 4, 5, 8, and 9 to view stratigraphic section

Former dam site

Spring

Streamflow-gaging station

U.S. Geological Survey 

11501000

Oregon Water Resources Department

U.S. DEPARTMENT OF THE INTERIOR

U.S. GEOLOGICAL SURVEY

Prepared in cooperation with the

UNIVERSITY OF OREGON, and the

U.S. FISH AND WILDLIFE SERVICE

 SCIENTIFIC INVESTIGATIONS REPORT 2014−5223

Geomorphic surfaces—PLATE 1

O'Connor, J.E., McDowell, P.F., Lind, Pollyanna, Rasmussen, C.G., Keith, M.K., 2015, Geomorphology and 

Flood-Plain Vegetation of the Sprague and Lower Sycan Rivers, Klamath Basin, Oregon

SCALE 1:100,000

0 2 4 6 8 10 MILES

0 2 4 6 8 10 KILOMETERS

121°50’

121°40’

121°30’ 121°20’ 121°10’

121°

121°50’

121°40’

121°30’

121°20’

121°10’

121°

42°35’

42°30’

42°25’

42°25’

42°30’

42°35’

42°20’

Geomorphic Surfaces of the Sprague and Lower Sycan Rivers, Oregon

By

Jim E. O’Connor, Patricia F. McDowell, Pollyanna Lind, Christine G. Rasmussen, and Mackenzie K. Keith

2015

Base compiled from Watershed Sciences, Inc. (2005) digital data, 1-meter resolution (along valley floor); 

U.S. Geological Survey digital data, 10-meter resolution (outside valley floor). Coordinate reference system: 

Universal Transverse Mercator projection, Zone 10N, horizontal datum is North American Datum of 1983.

Geologic linework was digitized at a scale of 1:3,000 but the accuracy

of the contacts varies depending on location and geomorphic unit.